Lenco Component Parts
In general, all LENCO transmissions are a planetary design. Planetary transmissions rely on a central sun gear to provide a 1:1 direct drive ratio once shifted from the launch ratio.
In order to achieve an underdrive first gear launch ratio the LENCO transmission relys on planet gears which rotate around the sun gear.
Each sun and planet gearset provides two speeds. Those two speeds are (1) the lower underdrive ratio and (2) the direct 1:1 final lock-up drive ratio.
Each LENCO transmission is thus a two speed and is housed in one dedicated two speed.
We acheive more than two speeds by combining multiple cases.
|For example, a three speed requires two cases.|
|A four speed requires three cases.|
A five speed requires four cases, and a six speed requires five cases.
Since each case contains one gearset and provides both underdrive and direct drive, multiple cases (gearsets) provide multiple underdrive ratios.
You must multiply each cases underdrive ratio in order to determine the first gear ratio.
By multiplying these three ratios you come up with a 2.46 first gear ratio. Second gear ratio is 1.80 and third gear is a 1.31 ratio. Final drive ratio is 1:1.
Multiply all three gearset ratios to determine the first gear ratio of 2.46:1. Multiply the two rear case gearset ratios to determine the second gear ratio of 1.80:1. The gearset in the third case alone, 1.31:1, determines the third gear ratio. All three units shifted equal final drive ratio of 1:1.
The internal action of a LENCO is such that when the transmission is in first gear the dedicated planet gear assembly provides the launch ratio. The planet gears are driven by an encompassing ring gear.
When the transmission is shifted a clutch pack compresses the rotating sun gear assembly to the direct drive central sun gear. Thus a 1:1 ratio is achieved.
Each case in succession, with its particular underdrive ratio, determines the immediate drive ratio.
Once all cases have been shifted the entire transmission assembly is locked in the final 1:1 direct drive ratio.
It is not necessary for the driver to disengage the clutch when shifting from ratio to ratio since all shifting is done with the engines clutch fully engaged.